Comparison of Upper and Lower Canine Retraction Rates Assisted by Flapless Laser Corticotomy.

Abstract

Introduction: One of the most frequent issues in extraction cases is the prolongedduration of orthodontic therapy and the slow rate of canine retraction. Aim: Thissecondary analysis study aimed to compare the rate of canine retraction in upperand lower canines facilitated with Flapless Laser corticotomy (FLC). Materials andMethods: The study included 56 canines from 14 patients (2 males /12 females) witha mean age of (20.4±2.5) years diagnosed with bimaxillary dentoalveolar protrusionand treated with 4 premolars extraction with upper and lower fixed appliances. Theintervention was applied in a split-mouth fashion, so before commencing the study, 2random computer-generated lists with a 1:1 allocation ratio were obtained to detect theside of intervention, these lists were concealed in opaque envelopes until the time ofintervention. All participants were allocated into 2 groups, I- (Maxillary canines: whichwere divided into two subgroups A. Control, B. FLC) and II- (Mandibular canines:which were divided into two subgroups A. Control B. FLC). FLC was applied on theexperimental sides before canine retraction by performing 6 holes with 3 mm of depthinto the alveolar bone on both mesial and distal sides of all canines, then canines’retraction was performed using closed-coil springs to obtain a force of 150 gm whileanchorage was augmented indirectly with TADs. The rate of canine retraction wasassessed at T0, T1, T2, and T3 (just before, 1 month, 2 months, and 3 months afterretraction), using 3-Dimentional digital casts. Only the statistical analysis expert wasblinded. Results: The results showed a statistically non-significant difference betweenall groups (upper and lower flapless laser corticotomy and control) in the change incanine retraction distance and monthly rate of Canine retraction. Conclusion: Therewere neither statistically nor clinically significant differences between upper and lowercanine retraction rates either by conventional method or assisted by FLC performed inthis study.